(1) Field of the Invention
The present invention relates to satellite communications and, more particularly, to personal safety devices
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98                Schlager, U.S. Pat. No. 5,963,130, Oct. 5, 1999, Self-locating remote monitoring system        Curcio, Joseph, U.S. Pat. No. 6,414,629, Jul. 2, 2002, Tracking Device        Burks U.S. Pat. No. 6,317,050 Nov. 13, 2001 Water entry alarm system        McClure, U.S. Pat. No. 6,439,941, Aug. 27, 2002, Automated fail-safe sea rescue flotation system        
The Schlager patent discusses a man-over-board system. The remote has a navigational receiver and a radio transmitter. The monitor has a radio base station for receiving the signal from the remote. The remote and monitor radios are in constant radio contact.
The alarm at the monitor is triggered when;                the radio signal between the two radios goes below a settable signal level (establishing a geo-fence), or        a GPS (navigational satellite) location is correlated to exceed a settable distance, or        the transmit/receive time between the units exceeds a settable limit, or        a curfew time is exceeded, or        a sensor on the remote is triggered (by water, smoke, heartbeat or other sensor), or        the person hit a “panic button”.        
The remote and monitor radios must have line-of-site. The embodiments as a child monitor at a pool or a medical patient monitor demonstrate the short range of the device. In the man-over-board embodiment, the monitor has a display showing location of the remote.
All these embodiments require the remote and monitor radio are within line-of-sight. This means that the system is a very local. The remote is also very battery limited because of the need for constant radio communications. Ground or sea-level radio systems are very limited in distance; it is a few miles at best and a few hundred feet in swells.
The embodiment of a wireless (cell) phone or radio-telephone in the remote which allows it to call a preset 911-like number imposes a similar line-of-sight restriction as of having of a monitor with a cellular transceiver. That is, if the remote does not have line-of-sight with the cell system or radio-telephone of the monitor, the remote is lost. At sea or on land, this is limited to a few miles at best.
The monitor, especially in the case of man-over-board embodiment, must have radio equipment that is installed, manned, powered, and maintained. These is a burden for any vessel and useless to a lone-pilot or life raft situation. In any situation where the monitor must have working equipment and competence in its usage for this system to work, the remote is at risk even if the remote equipment is good working order.
Another embodiment is this system's use as a weather monitor; again we are at the mercy of a working monitor to gather then information from the remotes via line-of sight radio. To work over any large area we must install an infrastructure of monitor sites.
The Wearable Satellite Tracker has the novel approach from Schlager that it does not require any local monitoring. There is no local monitoring equipment that will need monitored, powered or maintained. In the Wearable Satellite Tracker all monitoring of the remote is done over satellite to a Central Tracking Monitor that monitor all Wearable Satellite Tracker in the world or with a spec.
Monitoring the Wearable Satellite Tracker by satellite allows it to be monitored any where in the world for a central point where monitoring resources can be focused to provide full period service with qualified personnel.
Nowhere is the term satellite used in the Schlager patent. The Schlager patent is limited to a one remote to one monitor ratio.
Curcio, Joseph, U.S. Pat. No. 6,414,629, Jul. 2, 2002, Tracking Device
This patent has a GPS tracking unit and transmitter on the remote and a local receiver. The local receiver determines the heading and direction to the remote. The receiver then provides the monitor a compass heading and distance to the remote. The radio communications path between the remote and monitor radios is line-of-sight. The monitor must be paying attention to the device and the tracking equipment must be in good working order.
The difference is that Curcio patent is for a local tracking, the remote and monitor must have radio with line-of-sight between the two. In the case of a lone-pilot or no one noticing someone falls overboard, the device will not work. Line of sight on a flat surface like a calm ocean is limited to a few miles if the monitor has an antenna on a very tall mast on a ship. However, if the seas have swells the line of site distance is very limited.
If the ship, which contains the monitoring device, should sink, this device is useless in informing authorities of the location of the survivors. Additionally, at sea, this device requires that each vessel or using the device must buy equipment for both the remote and monitor. The monitor equipment must be properly installed, powered, manned and maintained. If the monitors circuits, batteries, antenna should fail, the remote is useless. Full redundancy of monitoring equipment is needed to ensure a high reliability of service. This is a sufficient cost for each vessel to bear in terms of equipment, space and manpower. The device is also useless for lone-ship pilots, air-plane crews, or life rafts adrift where no monitor is available.
On land the tracking distance for this system will be very limited by ground obstructions and only good for short distances when the monitor equipment is available, manned, powered and maintained.
Burks U.S. Pat. No. 6,317,050 Nov. 13, 2001 Water entry alarm system
Burks water enter alarm system is a harness intent for children in a pool area. The remote (child with a water entry harness on) will trigger the alarm on the monitor radio if the remote does one of the following;                enters the water, or        the belts are unhooked, or        the radio signal from remote to monitor is absent.        
This patent is also dependent on a line-of-site radio transmission between the remote and monitor. There is always a local monitor radio receiver needed. The patent is intended only for short ranges for children in a local pool or water danger area. It does not envision itself as a global tracking for rescue service, but as a very local monitor.
It is therefore an object of the Wearable Satellite Tracker to provide a greater degree of personal safety by providing a central management of the satellite tracker rather than relying on local availability of monitoring equipment and personal seen in previous inventions